To satisfy the requirements of amputated persons of the 1980s, prosthetic feet providing energy return were launched on the market, these, by using composite materials such as carbon fibre, being able to store energy during the initial foot bearing phase, i.e. during so-called loading, and to return it during the subsequent ground support phase, known as the response, before take-off.
Typically, such prosthetic feet present an L-shaped lamina defining the front part of the foot, and a rear lamina defining the rear part or heel of the foot.
These prosthetic feet on the one hand provide good energy absorption during the initial part of the bearing state, hence ensuring good rear flexure of the foot, however they present minimal plantar flexure because of two factors:                in the final bearing phase, during toe-off, when ground contact takes place only via the tip of the foot front, the carbon fibre laminas of traditional prosthetic feet no longer function, i.e. no longer return energy, hence not enabling the user to make the final fundamental propulsive thrust;        the foot efficiency, i.e. the ratio of energy absorbed to energy returned by the prosthetic foot, is usually about 70%.        
The technical aim of the present invention is therefore to provide a prosthetic foot which enables the stated technical drawbacks of the known art to be eliminated.